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Bunch-length measurement at a bunch-by-bunch rate based on time–frequency-domain joint analysis techniques and its application
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作者 Hong-Shuang Wang Xing Yang +2 位作者 Yong-Bin Leng Yi-Mei Zhou Ji-Gang Wang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第4期165-175,共11页
This paper presents a new technique for measuring the bunch length of a high-energy electron beam at a bunch-by-bunch rate in storage rings.This technique uses the time–frequency-domain joint analysis of the bunch si... This paper presents a new technique for measuring the bunch length of a high-energy electron beam at a bunch-by-bunch rate in storage rings.This technique uses the time–frequency-domain joint analysis of the bunch signal to obtain bunch-by-bunch and turn-by-turn longitudinal parameters,such as bunch length and synchronous phase.The bunch signal is obtained using a button electrode with a bandwidth of several gigahertz.The data acquisition device was a high-speed digital oscilloscope with a sampling rate of more than 10 GS/s,and the single-shot sampling data buffer covered thousands of turns.The bunch-length and synchronous phase information were extracted via offline calculations using Python scripts.The calibration coefficient of the system was determined using a commercial streak camera.Moreover,this technique was tested on two different storage rings and successfully captured various longitudinal transient processes during the harmonic cavity debugging process at the Shanghai Synchrotron Radiation Facility(SSRF),and longitudinal instabilities were observed during the single-bunch accumulation process at Hefei Light Source(HLS).For Gaussian-distribution bunches,the uncertainty of the bunch phase obtained using this technique was better than 0.2 ps,and the bunch-length uncertainty was better than 1 ps.The dynamic range exceeded 10 ms.This technology is a powerful and versatile beam diagnostic tool that can be conveniently deployed in high-energy electron storage rings. 展开更多
关键词 Bunch-by-bunch diagnostic Bunch-length measurement Synchronous phase measurement Joint time–frequency-domain analysis Longitudinal instability
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Unknown Environment Measurement Mapping by Unmanned Aerial Vehicle Using Kalman Filter-Based Low-Cost Estimated Parallel 8-Beam LIDAR
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作者 Mohamed Rabik Mohamed Ismail Muthuramalingam Thangaraj +2 位作者 Khaja Moiduddin Zeyad Almutairi Mustufa Haider Abidi 《Computers, Materials & Continua》 SCIE EI 2024年第9期4263-4279,共17页
The measurement and mapping of objects in the outer environment have traditionally been conducted using ground-based monitoring systems,as well as satellites.More recently,unmanned aerial vehicles have also been emplo... The measurement and mapping of objects in the outer environment have traditionally been conducted using ground-based monitoring systems,as well as satellites.More recently,unmanned aerial vehicles have also been employed for this purpose.The accurate detection and mapping of a target such as buildings,trees,and terrains are of utmost importance in various applications of unmanned aerial vehicles(UAVs),including search and rescue operations,object transportation,object detection,inspection tasks,and mapping activities.However,the rapid measurement and mapping of the object are not currently achievable due to factors such as the object’s size,the intricate nature of the sites,and the complexity of mapping algorithms.The present system introduces a costeffective solution for measurement and mapping by utilizing a small unmanned aerial vehicle(UAV)equipped with an 8-beam Light Detection and Ranging(LiDAR)system.This approach offers advantages over traditional methods that rely on expensive cameras and complex algorithm-based approaches.The reflective properties of laser beams have also been investigated.The system provides prompt results in comparison to traditional camerabased surveillance,with minimal latency and the need for complex algorithms.The Kalman estimation method demonstrates improved performance in the presence of noise.The measurement and mapping of external objects have been successfully conducted at varying distances,utilizing different resolutions. 展开更多
关键词 8 beam LiDAR UAV measureMENT MAPPING Kalman filter
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Non-Kramers doublet ground state in a quaternary cubic compound PrRu_(2)In_(2)Zn_(18) investigated by ultrasonic measurements
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作者 张化远 Kazuhei Wakiya +2 位作者 Mitsuteru Nakamura Masahito Yoshizawa Yoshiki Nakanish 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期405-411,共7页
We performed ultrasonic measurements on a quaternary cubic compound PrRu_(2)In_(2)Zn_(18) to explore the ground state properties derived from non-Kramers Γ_(3) doublet of Pr^(3+).PrRu_(2)In_(2)Zn_(18) is a quaternary... We performed ultrasonic measurements on a quaternary cubic compound PrRu_(2)In_(2)Zn_(18) to explore the ground state properties derived from non-Kramers Γ_(3) doublet of Pr^(3+).PrRu_(2)In_(2)Zn_(18) is a quaternary derivative of the ternary compound PrRu_(2)Zn_(20) that exhibits a structural phase transition at T_S=138 K.In PrRu_(2)In_(2)Zn_(18),the Zn atoms at the 16c site in PrRu_(2)Zn_(20) are selectively replaced by In atoms.A monotonic increase was observed in the temperature dependence of elastic constants C_L=(C_(11)+2C_(12)+4C_(44))/3 and C_(T)=(C_(11)-C_(12)+C_(44))/3 in the temperature range around T_(S) to which an elastic softening was observed in(C_(11)-C_(12))/2 for PrRu_(2)Zn_(20).The disappearance of the softening indicates that the structural transition in PrRu_(2)Zn_(20) is suppressed by the substitution of Zn ions by In ones with a larger ionic radius.Alternatively,the C_(T) of PrRu_(2)In_(2)Zn_(18) exhibits a precursor Curie-type elastic softening toward low temperatures being responsible for the non-Kramers Γ_(3) ground state.We discuss the ground state and the evolution of the elastic properties of the different single-crystal samples of PrRu_(2)In_(2)Zn_(18) grown under different conditions. 展开更多
关键词 ultrasonic measurements non-Kramers doublet structural phase transition crystalline electric field effect
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Protected simultaneous quantum remote state preparation scheme by weak and reversal measurements in noisy environments
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作者 Mandal Manoj Kumar Choudhury Binayak S. Samanta Soumen 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期169-177,共9页
We discuss a quantum remote state preparation protocol by which two parties, Alice and Candy, prepare a single-qubit and a two-qubit state, respectively, at the site of the receiver Bob. The single-qubit state is know... We discuss a quantum remote state preparation protocol by which two parties, Alice and Candy, prepare a single-qubit and a two-qubit state, respectively, at the site of the receiver Bob. The single-qubit state is known to Alice while the two-qubit state which is a non-maximally entangled Bell state is known to Candy. The three parties are connected through a single entangled state which acts as a quantum channel. We first describe the protocol in the ideal case when the entangled channel under use is in a pure state. After that, we consider the effect of amplitude damping(AD) noise on the quantum channel and describe the protocol executed through the noisy channel. The decrement of the fidelity is shown to occur with the increment in the noise parameter. This is shown by numerical computation in specific examples of the states to be created. Finally, we show that it is possible to maintain the label of fidelity to some extent and hence to decrease the effect of noise by the application of weak and reversal measurements. We also present a scheme for the generation of the five-qubit entangled resource which we require as a quantum channel. The generation scheme is run on the IBMQ platform. 展开更多
关键词 multi-qubit entangled channel quantum remote state preparation noisy environments weak and reversal measurements
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Adherence to Physical Measures during the SARS-COV2 Pandemic by Haemodialysis Patients in a Burkina Faso Tertiary Hospital: A Cross-Sectional Survey
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作者 Bonzi Y. Juste Zoehinga Patrice +4 位作者 Sourabie Oumar Kabore D. Dieudonne Hien Siebou Sawadogo Amidou Coulibaly Gerard 《Open Journal of Nephrology》 2024年第3期375-385,共11页
Context: COVID-19 can spread rapidly in haemodialysis centres, leading to fatal outcomes. Implementing physical measures is crucial in limiting the spread of infection. Aims: To assess adherence to physical measures a... Context: COVID-19 can spread rapidly in haemodialysis centres, leading to fatal outcomes. Implementing physical measures is crucial in limiting the spread of infection. Aims: To assess adherence to physical measures against SARS-Cov2 in haemodialysis patients. Methods and Material: From 13 to 19 July 2021, we administered the questionnaire to haemodialysis patients during or immediately after the dialysis session. The dependent variables were adherence to wearing masks, hand washing outside the dialysis centre, social distancing of at least 1.5 meters, and cough and sneeze hygiene. Statistical Analysis Used: Data were analyzed using Epi info software;descriptive statistics were presented as mean, headcount, and percentage;related factors were determined by multi-logistic regression. The significance level was 5%. The Health Research Ethics Committee approved the research protocol. Results: 142 patients were included (mean age: 42.5 ± 14 years). Wearing masks, hand-washing, social distancing, and coughing and sneezing hygiene were observed by 88%, 75%, 47%, and 60% of patients, respectively. Conclusion: Wearing masks was the most respected physical measure, while social distancing was the least respected. 展开更多
关键词 Physical measures COVID-19 HAEMODIALYSIS SARS-COV2 Tertiary Hospital Sub-Saharan Africa
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A Synergistic Multi-Attribute Decision-Making Method for Educational Institutions Evaluation Using Similarity Measures of Possibility Pythagorean Fuzzy Hypersoft Sets
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作者 Khuram Ali Khan Saba Mubeen Ishfaq +1 位作者 Atiqe Ur Rahman Salwa El-Morsy 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期501-530,共30页
Due to the numerous variables to take into account as well as the inherent ambiguity and uncertainty,evaluating educational institutions can be difficult.The concept of a possibility Pythagorean fuzzy hypersoft set(pP... Due to the numerous variables to take into account as well as the inherent ambiguity and uncertainty,evaluating educational institutions can be difficult.The concept of a possibility Pythagorean fuzzy hypersoft set(pPyFHSS)is more flexible in this regard than other theoretical fuzzy set-like models,even though some attempts have been made in the literature to address such uncertainties.This study investigates the elementary notions of pPyFHSS including its set-theoretic operations union,intersection,complement,OR-and AND-operations.Some results related to these operations are also modified for pPyFHSS.Additionally,the similarity measures between pPyFHSSs are formulated with the assistance of numerical examples and results.Lastly,an intelligent decision-assisted mechanism is developed with the proposal of a robust algorithm based on similarity measures for solving multi-attribute decision-making(MADM)problems.A case study that helps the decision-makers assess the best educational institution is discussed to validate the suggested system.The algorithmic results are compared with the most pertinent model to evaluate the adaptability of pPyFHSS,as it generalizes the classical possibility fuzzy set-like theoretical models.Similarly,while considering significant evaluating factors,the flexibility of pPyFHSS is observed through structural comparison. 展开更多
关键词 Hypersoft set Pythagorean fuzzy hypersoft set computational complexity multi-attribute decision-making optimization similarity measures uncertainty
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Correlation between the rock mass properties and maximum horizontal stress:A case study of overcoring stress measurements
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作者 Peng Li Meifeng Cai +2 位作者 Shengjun Miao Yuan Li Yu Wang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期39-48,共10页
Understanding the mechanical properties of the lithologies is crucial to accurately determine the horizontal stress magnitude.To investigate the correlation between the rock mass properties and maximum horizontal stre... Understanding the mechanical properties of the lithologies is crucial to accurately determine the horizontal stress magnitude.To investigate the correlation between the rock mass properties and maximum horizontal stress,the three-dimensional(3D)stress tensors at 89 measuring points determined using an improved overcoring technique in nine mines in China were adopted,a newly defined characteristic parameter C_(ERP)was proposed as an indicator for evaluating the structural properties of rock masses,and a fuzzy relation matrix was established using the information distribution method.The results indicate that both the vertical stress and horizontal stress exhibit a good linear growth relationship with depth.There is no remarkable correlation between the elastic modulus,Poisson's ratio and depth,and the distribution of data points is scattered and messy.Moreover,there is no obvious relationship between the rock quality designation(RQD)and depth.The maximum horizontal stress σ_(H) is a function of rock properties,showing a certain linear relationship with the C_(ERP)at the same depth.In addition,the overall change trend of σ_(H) determined by the established fuzzy identification method is to increase with the increase of C_(ERP).The fuzzy identification method also demonstrates a relatively detailed local relationship betweenσ_H and C_(ERP),and the predicted curve rises in a fluctuating way,which is in accord well with the measured stress data. 展开更多
关键词 overcoring stress measurements elastic modulus Poisson's ratio rock quality designation maximum horizontal stress fuzzy identification
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STUDY ON MEASUREMENT OF WOOD SURFACEROUGHNESS BY COMPUTER VISION
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作者 Zhao XuezengNortheast Forestry University 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1992年第1期75-81,共7页
The working processes, machining devices and tools, cutting amount, consumption of materials, productivity and quality of products are directly affected by wood surface roughness. This paper gives an extensive review ... The working processes, machining devices and tools, cutting amount, consumption of materials, productivity and quality of products are directly affected by wood surface roughness. This paper gives an extensive review of methods used previously to measure wood surface roughness, and concludes that computer vision is the most suitable technique. The preliminary study shows that computer vision method has the advantages of a noncontact, three-dimensional measurement, high speed and well correlates with stylus tracing method. This method can be used in classification and in-time measurement of wood surface roughness after being improved. 展开更多
关键词 WOOD Surface roughness measureMENT computer vision.
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Voices that matter:The impact of patient-reported outcome measures on clinical decision-making
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作者 Naveen Jeyaraman Madhan Jeyaraman +2 位作者 Swaminathan Ramasubramanian Sangeetha Balaji Sathish Muthu 《World Journal of Methodology》 2025年第2期54-61,共8页
The critical role of patient-reported outcome measures(PROMs)in enhancing clinical decision-making and promoting patient-centered care has gained a profound significance in scientific research.PROMs encapsulate a pati... The critical role of patient-reported outcome measures(PROMs)in enhancing clinical decision-making and promoting patient-centered care has gained a profound significance in scientific research.PROMs encapsulate a patient's health status directly from their perspective,encompassing various domains such as symptom severity,functional status,and overall quality of life.By integrating PROMs into routine clinical practice and research,healthcare providers can achieve a more nuanced understanding of patient experiences and tailor treatments accordingly.The deployment of PROMs supports dynamic patient-provider interactions,fostering better patient engagement and adherence to tre-atment plans.Moreover,PROMs are pivotal in clinical settings for monitoring disease progression and treatment efficacy,particularly in chronic and mental health conditions.However,challenges in implementing PROMs include data collection and management,integration into existing health systems,and acceptance by patients and providers.Overcoming these barriers necessitates technological advancements,policy development,and continuous education to enhance the acceptability and effectiveness of PROMs.The paper concludes with recommendations for future research and policy-making aimed at optimizing the use and impact of PROMs across healthcare settings. 展开更多
关键词 Patient-reported outcome measures Clinical decision-making Patient-centered care Healthcare technology Data management Policy development
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Variations in quantifying patient reported outcome measures to estimate treatment effect
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作者 Sathish Muthu Srujun Vadranapu 《World Journal of Methodology》 2025年第2期44-53,共10页
In the practice of healthcare,patient-reported outcomes(PROs)and PRO measures(PROMs)are used as an attempt to observe the changes in complex clinical situations.They guide us in making decisions based on the evidence ... In the practice of healthcare,patient-reported outcomes(PROs)and PRO measures(PROMs)are used as an attempt to observe the changes in complex clinical situations.They guide us in making decisions based on the evidence regarding patient care by recording the change in outcomes for a particular treatment to a given condition and finally to understand whether a patient will benefit from a particular treatment and to quantify the treatment effect.For any PROM to be usable in health care,we need it to be reliable,encapsulating the points of interest with the potential to detect any real change.Using structured outcome measures routinely in clinical practice helps the physician to understand the functional limitation of a patient that would otherwise not be clear in an office interview,and this allows the physician and patient to have a meaningful conver-sation as well as a customized plan for each patient.Having mentioned the rationale and the benefits of PROMs,understanding the quantification process is crucial before embarking on management decisions.A better interpretation of change needs to identify the treatment effect based on clinical relevance for a given condition.There are a multiple set of measurement indices to serve this effect and most of them are used interchangeably without clear demarcation on their differences.This article details the various quantification metrics used to evaluate the treatment effect using PROMs,their limitations and the scope of usage and implementation in clinical practice. 展开更多
关键词 Patient-reported outcome measures Treatment effect Minimal clinical important difference Patient-accepted symptom state Minimum detectable change ORTHOPEDICS
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Research into Uncertainty in Measurement of Seawater Chemical Oxygen Demand by Potassium Iodide-Alkaline Potassium Permanganate Determination Method 被引量:1
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作者 张世强 郭长松 《Marine Science Bulletin》 CAS 2007年第2期18-24,共7页
Using the glucose and L-glutamic-acid to prepare the standard substance according to the ratio of 1:1, and the artificial seawater and the standard substance to prepare a series of standard solutions, the distributio... Using the glucose and L-glutamic-acid to prepare the standard substance according to the ratio of 1:1, and the artificial seawater and the standard substance to prepare a series of standard solutions, the distribution pattern of uncertainty in measurement of seawater COD is obtained based on the measured results of the series of standard solutions by the potassium iodide-alkaline potassium permanganate determination method. The distribution pattern is as follows: Uncertainty in measurement is big and not constant at the high end, but small and constant at the low end. 展开更多
关键词 potassium iodide-alkaline potassium permanganate determination COD uncertainty in measurement
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Measurement of Refractive Indices of (Al_xGa_(1-x))_(0.51)In_(0.49)P Grown by Low Pressure Organometallic Vapor Phase Epitaxy
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作者 廉鹏 马骁宇 +1 位作者 张广泽 陈良惠 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2001年第4期398-401,共4页
The refractive indices of disordered (Al xGa 1-x ) 0 51 In 0 49 P,which is grown by low-pressure organometallic vapor phase epitaxy and lattice-matched to GaAs substrate,have been determined by measurin... The refractive indices of disordered (Al xGa 1-x ) 0 51 In 0 49 P,which is grown by low-pressure organometallic vapor phase epitaxy and lattice-matched to GaAs substrate,have been determined by measuring their reflectance spectra when the wavelength ranges between 0 5 to 2 5 micrometer.A single-oscillator dispersion model is used to verify the experiment data and calculate the reflectance spectrum.The refractive indices are used to analyze the waveguide of strain quantum well GaInP/AlGaInP visible laser diode.The simulated far field pattern is consistent with the experimental results very well. 展开更多
关键词 LP-OMVPE refractive index measureMENT GAINP/ALGAINP
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Damage by wind-blown sand and its control measures along the Taklimakan Desert Highway in China 被引量:15
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作者 LI Congjuan WANG Yongdong +4 位作者 LEI Jiaqiang XU Xinwen WANG Shijie FAN Jinglong LI Shengyu 《Journal of Arid Land》 SCIE CSCD 2021年第1期98-106,共9页
Desertification is one of the most serious environmental problems in the world,especially in the arid desert regions.Combating desertification,therefore,is an urgent task on a regional or even global scale.The Taklima... Desertification is one of the most serious environmental problems in the world,especially in the arid desert regions.Combating desertification,therefore,is an urgent task on a regional or even global scale.The Taklimakan Desert in China is the second largest mobile desert in the world and has been called the''Dead Sea''due to few organisms can exist in such a harsh environment.The Taklimakan Desert Highway,the longest desert highway(a total length of 446 km)across the mobile desert in the world,was built in the 1990s within the Taklimakan Desert.It has an important strategic significance regarding oil and gas resources exploration and plays a vital role in the socio-economic development of southern Xinjiang,China.However,wind-blow sand seriously damages the smoothness of the desert highway and,in this case,mechanical sand control system(including sand barrier fences and straw checkerboards)was used early in the life of the desert highway to protect the road.Unfortunately,more than 70%of the sand barrier fences and straw checkerboards have lost their functions,and the desert highway has often been buried and frequently blocked since 1999.To solve this problem,a long artificial shelterbelt with the length of 437 km was built along the desert highway since 2000.However,some potential problems still exist for the sustainable development of the desert highway,such as water shortage,strong sandstorms,extreme environmental characteristics and large maintenance costs.The study aims to provide an overview of the damages caused by wind-blown sand and the effects of sand control measures along the Taklimakan Desert Highway.Ultimately,we provide some suggestions for the biological sand control system to ensure the sustainable development of the Taklimakan Desert Highway,such as screening drought-resistant species to reduce the irrigation requirement and ensure the sound development of groundwater,screening halophytes to restore vegetation in the case of soil salinization,and planting cash crops,such as Cistanche,Wolfberry,Apocynum and other cash crops to decrease the high cost of maintenance on highways and shelterbelts. 展开更多
关键词 wind-blown sand sand barrier fences artificial shelterbelt mechanical sand control measure biological sand control measure sustainable development Taklimakan Desert Highway
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Aerodynamics of indirect thrust measurement by the impulse method 被引量:12
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作者 Cheng-Kang Wu Hai-Xing Wang +2 位作者 Xian Meng Xi Chen Wen-Xia Pan 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2011年第2期152-163,共12页
The aerodynamic aspects of indirect thrust measurement by the impulse method have been studied both experimentally and numerically. The underlying basic aerodynamic principle is outlined, the phenomena in subsonic, su... The aerodynamic aspects of indirect thrust measurement by the impulse method have been studied both experimentally and numerically. The underlying basic aerodynamic principle is outlined, the phenomena in subsonic, supersonic and arc-heated jets are explored, and factors affecting the accuracy of the method are studied and discussed. Results show that the impulse method is reliable for indirect thrust measurement if certain basic requirements are met, and a simple guideline for its proper application is given. 展开更多
关键词 Thrust measurement Impulse method Aerodynamic features Cold jet Arc-heated jet
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Quantum Measurement of Single Electron State by a Mesoscopic Detector
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作者 胡学宁 骆钧炎 李新奇 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第2期218-222,共5页
A realistic measurement setup for a system such system measured by a mesoscopie detector,is theoretically as a charged two-state (qubit) or multi-state quantum studied. To properly describe the measurement-induced b... A realistic measurement setup for a system such system measured by a mesoscopie detector,is theoretically as a charged two-state (qubit) or multi-state quantum studied. To properly describe the measurement-induced back-action,a detailed-balance preserved quantum master equation treatment is developed. The established framework is applicable for arbitrary voltages and temperatures. 展开更多
关键词 quantum measurement detailed balance RELAXATION
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A distributed measurement method for in-situ soil moisture content by using carbon-fiber heated cable 被引量:14
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作者 Dingfeng Cao Bin Shi +3 位作者 Honghu Zhu Guangqing Wei Shen-En Chen Junfan Yan 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2015年第6期700-707,共8页
Moisture content is a fundamental physical index that quantifies soil property and is closely associatedwith the hydrological, ecological and engineering behaviors of soil. To measure in-situ soil moisturecontents, a ... Moisture content is a fundamental physical index that quantifies soil property and is closely associatedwith the hydrological, ecological and engineering behaviors of soil. To measure in-situ soil moisturecontents, a distributed measurement system for in-situ soil moisture content (SM-DTS) is introduced.The system is based on carbon-fiber heated cable (CFHC) technology that has been developed to enhancethe measuring accuracy of in-situ soil moisture content. Using CFHC technique, a temperature characteristicvalue (Tt) can be defined from temperatureetime curves. A relationship among Tt, soil thermalimpedance coefficient and soil moisture content is then established in laboratory. The feasibility of theSM-DTS technology to provide distributed measurements of in-situ soil moisture content is verifiedthrough field tests. The research reported herein indicates that the proposed SM-DTS is capable ofmeasuring in-situ soil moisture content over long distances and large areas. 展开更多
关键词 In-situ soil moisture content Distributed measurement Carbon-fiber heated cable (CFHC) Fiber-optic sensing
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Measurement of mouse liver glutathione S-transferase activity by the integrated method 被引量:10
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作者 廖飞 李甲初 +2 位作者 康格非 曾昭淳 左渝萍 《Journal of Medical Colleges of PLA(China)》 CAS 2003年第5期295-300,共6页
Objective: The integrated method was investigated to measure Vm/Km of mouse liver glutathione S-transfer-ase (GST) activity on GSH and 7-Cl-4-nitrobenzofurazozan. Methods: Presetting concentration of one substrate twe... Objective: The integrated method was investigated to measure Vm/Km of mouse liver glutathione S-transfer-ase (GST) activity on GSH and 7-Cl-4-nitrobenzofurazozan. Methods: Presetting concentration of one substrate twenty-fold above the other's and taking maximum product absorbance Am as parameter while Km as constant, Vm/Km was obtained by nonlinear fitting of GST reaction curve to the integrated Michaelis-Menten equation In [Am/(Am -Ai)] + Ai/ ( ξ× Km ) = ( Vm/Km )×ti (1). Results: Vm/Km for GST showed slight dependence on initial substrate concentration and data range, but it was resistant to background absorbance, error in reaction origin and small deviation in presetting Km. Vm/Km was proportional to the amount of GST with upper limit higher than that by initial rate. There was close correlation between Vm/Km and initial rate of the same GST. Consistent results were obtained by this integrated method and classical initial rate method for the measurement of mouse liver GST. Conclusion: With the concentration of one substrate twenty-fold above the other's, this integrated method was reliable to measure the activity of enzyme on two substrates , and substrate concentration of the lower one close to its apparent Km was able to be used. 展开更多
关键词 integrated method glutathione S-transferase nonlinear fitting reaction curve predictor variable enzyme activity measurement
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Temperature and light tolerance of representative brown,green and red algae in tumble culture revealed by chlorophyll fluorescence measurements 被引量:4
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作者 PANG Shaojun SHAN Tifeng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2008年第4期137-146,共10页
Laminaria japonica, Undaria pinnatifida, Ulva lactuca, Grateloupia turuturu and Palmaria palmata are suitable species that fit the requirements of a seaweed-animal integrated aquaculture system in terms of their viabl... Laminaria japonica, Undaria pinnatifida, Ulva lactuca, Grateloupia turuturu and Palmaria palmata are suitable species that fit the requirements of a seaweed-animal integrated aquaculture system in terms of their viable biomass, rapid growth and promising nutrient uptake rates. In this investigation, the responses of the optimal chlorophyll fluorescence yield of the five algal species in tumble culture were assessed at a temperature range of 10 - 30℃. The results revealed that Ulva lactuca was the most resistant species to high temperature, withstanding 30℃ for 4 h without apparent decline in the optimal chlorophyll fluorescence yield . While the arctic alga Palmaria palmata was the most vulnerable one, showing significant decline in the optimal chlorophyll fluorescence yield at 25℃ for 2 h. The cold-water species Laminaria japonica, however, demonstrated strong ability to cope with higher temperature (24 -26℃ ) for shorter time (within 24 h) without significant decline in the optimal chlorophyll fluorescence yield . Grateloupia turuturu showed a general decrease in the optimal chlorophyll fluorescence yield with the rising temperature from 23 to 30℃ , similar to the temperate kelp Undaria pinnatifida. Changes of chlorophyll fluorescence yields of these algae were characterized differently indicating the existence of species-unique strategy to cope with high light. Measurements of the optimal chlorophyll fluorescence yield after short exposure to direct solar irradiance revealed how long these exposures could be without significant photoinhibition or with promising recovery in photosynthetic activities. Seasonal pattern of alternation of algal species in tank culture in the Northern Hemisphere at the latitude of 36°N was proposed according to these basic measurements. 展开更多
关键词 seaweeds chlorophyll fluorescence measurements Pulse Amplitude Modulation temperature tolerance integrated aquaculture
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A NOTE ON PERTURBATION OF NON-SYMMETRIC DIRICHLET FORMS BY SIGNED SMOOTH MEASURES 被引量:3
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作者 陈传钟 《Acta Mathematica Scientia》 SCIE CSCD 2007年第1期219-224,共6页
This article discusses the perturbation of a non-symmetric Dirichlet form, (ε, D(ε)), by a signed smooth measure u, where u=u1 -u2 with u1 and u2 being smooth measures. It gives a sufficient condition for the pe... This article discusses the perturbation of a non-symmetric Dirichlet form, (ε, D(ε)), by a signed smooth measure u, where u=u1 -u2 with u1 and u2 being smooth measures. It gives a sufficient condition for the perturbed form (ε^u ,D(ε^u)) (for some a0 ≥ 0) to be a coercive closed form. 展开更多
关键词 Non-symmetric Dirichlet form signed smooth measure perturbation of Dirichlet form generalized Feynman-Kac semigroup
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A light field measurement system through PSF estimation by a morphology-based method 被引量:3
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作者 Lingbao Kong Panyu Zhou 《International Journal of Extreme Manufacturing》 SCIE EI 2021年第4期113-124,共12页
Light field imaging technology can obtain three-dimensional(3D)information of a test surface in a single exposure.Traditional light field reconstruction algorithms not only take a long time to trace back to the origin... Light field imaging technology can obtain three-dimensional(3D)information of a test surface in a single exposure.Traditional light field reconstruction algorithms not only take a long time to trace back to the original image,but also require the exact parameters of the light field system,such as the position and posture of a microlens array(MLA),which will cause errors in the reconstructed image if these parameters cannot be precisely obtained.This paper proposes a reconstruction algorithm for light field imaging based on the point spread function(PSF),which does not require prior knowledge of the system.The accurate PSF derivation process of a light field system is presented,and modeling and simulation were conducted to obtain the relationship between the spatial distribution characteristics and the PSF of the light field system.A morphology-based method is proposed to analyze the overlapping area of the subimages of light field images to identify the accurate spatial location of the MLA used in the system,which is thereafter used to accurately refocus light field imaging.A light field system is built to verify the algorithm’s effectiveness.Experimental results show that the measurement accuracy is increased over 41.0%compared with the traditional method by measuring a step standard.The accuracy of parameters is also improved through a microstructure measurement with a peak-to-valley value of 25.4%and root mean square value of 23.5%improvement.This further validates that the algorithm can effectively improve the refocusing efficiency and the accuracy of the light field imaging results with the superiority of refocusing light field imaging without prior knowledge of the system.The proposed method provides a new solution for fast and accurate 3D measurement based on a light field. 展开更多
关键词 light field deconvolution 3D measurement PSF estimation measurement accuracy MLA
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